Various approaches have been taken in the past in the design and construction of laminated insoles for shoes and particularly for athletic footwear which can be molded to the shape of the foot and wherein the laminations making up the insole are given different characteristics to the end of providing maximum comfort and stability. Of the approaches taken in the past, U.S. Pat. No. 4,187,621 to L. H. Cohen discloses an insole which is made up of layers of a closed cell polyethylene foam having high impact absorption, the bottom layer being of greater density than the top layer and the layers bonded together by heat prior to molding. U.S. Pat. No. 4,130,948 to H. D. Krug is directed to a multi-layered insole having a plurality of closed cell polyolefin or polyethylene foam layers wherein the specific gravity of the layers increases progressively from the bottom to the top layer. U.S. Pat. No. 3,825,017 to J. E. Scrima discloses a solid layer which is interpositioned between top and bottom foam layers. In U.S. Pat. No. 4,633,598 to Y. Moronaga et al, the insole has a plurality of layers of different hardness with the heel portion increasing in hardness from the top to the bottom layer. Other representative patents of interest are U.S. Pat. Nos. 2,808,663 to L. P. Frieder et al; 4,520,581 to J. M. Irwin et al; 4,513,518 to R. A. Jalbert et al; 4,522,777 to W. Peterson; 4,669,142 to G. C. Meyer; and 4,718,179 to D. N. Brown. Of these, Peterson, Irwin and Meyer are of interest for disclosing molding apparatus for "cast-in-place" insoles.
It is proposed in accordance with the present invention to provide for a custom insole adaptable for use in athletic footwear as well as medical applications and with particular characteristics which lend well for use in ski boots to achieve maximum stability and comfort; and further to provide for a novel and improved casting process for molding the insole to the foot of the wearer in a simple but highly effective manner.